弹−塑性基础边界两侧采空(留煤柱)基本顶板结构初次破断特征  

First fracture characteristics of main roof plate structure with goaf(coal pillar)on both sides and elastic-plastic foundation boundary

作　　者：陈冬冬[1] 李子健 谢生荣[1] 何富连[1] 罗昱 蒋再胜 马翔 李辉[1] CHEN Dongdong;LI Zijian;XIE Shengrong;HE Fulian;LUO Yu;JIANG Zaisheng;MA Xiang;LI Hui(School of Energy and Mining Engineering,China University of Mining and Technology-Beijing,Beijing 100083,China)

机构地区：[1]中国矿业大学(北京)能源与矿业学院,北京100083

出　　处：《煤炭学报》2024年第5期2195-2211,共17页Journal of China Coal Society

基　　金：国家自然科学基金资助项目(52004286,51974317,52074296)。

摘　　要：为了研究两侧采空留煤柱工程条件下基本顶板结构的断裂位态及工程指导意义,构建考虑实体煤弹塑性变形与两侧煤柱宽度及支撑能力弱化的基本顶板结构双塑化基础边界力学模型,基于有限差分算法与主弯矩破断准则系统计算了在非对称煤柱区和长边实体煤区的断裂线形态、区位属性及整体位态特征,并从7个层面、横纵向4对区域与传统模型对比,阐明新模型所得新结论及工程意义。结论如下:(1)两侧非对称煤柱参数对长边实体煤区域的基本顶主弯矩及破断位置影响小,但分别显著影响煤柱区的主弯矩大小、位置及断裂形态。两侧煤柱区(较强/宽煤柱区+较弱/窄煤柱区)基本顶断裂线形态有3类演化模式,随基本顶厚度及弹模增大而煤柱宽度、支撑能力及悬顶跨度减小,其变化规律为:非对称的“连续单弧形+连续单弧形”→“连续单弧形+开口间断双短弧形”→非对称的“开口间断双短弧形+开口间断双短弧形”。(2)长边实体煤区基本顶的断裂线主要有3类区位属性,随基本顶厚度及弹模增大而实体煤的塑性区宽度、塑化程度及悬顶跨度减小,其演变规律为:断裂线在塑性煤体区(C-S式)→弹塑性煤体分界区(C-TS式)→弹性煤体区(C-T式);(3)考虑断裂线区位属性,随基本顶厚度和弹模增大而煤柱宽度、支撑能力及悬顶跨度减小的基本顶全区域破断模式及演变规律为:C-S式的■→C-TS式的■→C-T式的■→C-T式的■→C-T式的■。针对研究两侧采空(煤柱)基本顶板结构破断的3类力学模型,从7个层面对比了3类模型的重要区别,从横向4个区域(开采区域的前方与后方、两侧煤柱区)与纵向4个区域(非对称遗留煤柱下伏、下伏开采空间出/进煤柱/体)阐明了其重要工程作用。In order to study the fracture position and engineering significance of the main roof plate structure under the condition of goaf on both sides(coal pillars),the double plasticized foundation boundary mechanical model of the main roof plate structure considering the elastic-plastic deformation of coal and the width and support capacity weakening ofcoal pillar on both sides is constructed.Based on the finite difference algorithm and the principal moment breaking cri-terion,the shape characteristics,location attributes and overall position characteristics of the main roof fault line above the asymmetric coal pillars area and the long side solid coal area are systematically calculated,and the new conclusions and important engineering significance of the new model are clarified by comparing with the traditional models from seven levels and four pairs of areas in transverse and longitudinal directions.The conclusions are as follows:①The asymmetric coal pillars parameters on both sides have little influence on the main roof principal bending moment and fracture position above the long side solid coal area,but significantly affect the principal bending moment,position and fracture shape of the main roof above the coal pillar areas respectively.There are three types of evolution patterns of the main roof fracture line above the coal pillar areas on both sides(strong/wide coal pillar area+weak/narrow coal pillar area).With the in-crease of main roof thickness and elastic modulus,while coal pillars width,coal pillar bearing capacity and working face span decrease,its evolution law is as follows:asymmetric“continuous single arc+continuous single arc”→“continuous single arc+open discontinuous double short arc”→asymmetric“open discontinuous double short arc+open discontinu-ous double short arc”.②The fracture line of the main roof above the long side solid coal area mainly has three types of location attributes.With the increase of main roof thickness and elastic modulus,while the plastic zone width and pla

关 键 词：遗留煤柱 基本顶 两侧采空 弹−塑性基础 板结构 

分 类 号：TD325[矿业工程—矿井建设]